ZX Engine Replacement

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rashmore
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ZX Engine Replacement

Post by rashmore »

OK, mine died Friday (ref bad vibrations...)
Have found a replacement, in a 405. It was driven to scrap yard, so managed to hear it running yesterday, but only briefly. (136k)
did notice that the leak off pipe on injector nearest to alterator end had been replaced and fitted with hard plastic pipe and then had a screw put in it ? thoughts on this ?
some oil deposit down front in centre area ?
didn't start first time, re heated glow plugs and fired up. not overly blue smokey, but there none the less.
Attending tonight to have a better look - any pointers on what to look for ?
Help gratefully received.
jeremy
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Post by jeremy »

From what I recall you've got bore/piston/ring trouble on your existing engine.
Have you thought about repairing it? i.e. re-boring and fitting new pistons, bearings etc - or purchasing a ready done short motor from one of the many reconditioners who advertise in Exchange and Mart? (fit while you wait etc offers) Many guarantee their work, as do some fitters of used engines.
I'd rather take that route than buying one from a scrapper - particularily if the thing had been run into the ground and neglected in the knowledge that when the MOt or something else expired it would be scrapped.
jeremy
rashmore
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Post by rashmore »

He offered it to me for £85 with turbo, which I thought was cheap...going to let me run for say 15 mins tonight to see smoke colour, noises etc. next to old slag heap so should be able to drive it about...
Need to see why it is in scrappers (assuming he tells the right story...) thought i could drive it to mine, swap over and then drive back...
Scally's scrap around the corner charge £250 for engine - 28 day warranty. £500 will supply and fit, incl new cambelt, oil, filter, anitfreeze.
Had thought about repair, but not sure on cost - assumed would be quite high. I don't mind doing the spanner work - figured easier to swap engine than pull current apart . Shame to get rid of car as uprated to berlingo brakes, body in good nick, plus been to see The Derv Doctor for mild tune.
Will try and locate local reconditioner to establish prices.
bxbodger
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Post by bxbodger »

Leave it well alone- if its been owned by someone who sticks a screw into the injector leak off rather than spend six quid on the proper pipe, imagine how little maintenance the rest of it has had.....and its smoking......!!!
An engine is possibly the only thing you should never buy from a scrapper!!
It will be complete rubbish, and no matter how cheap it is it will be a false economy!! Its probably not had an oil change since the last century.....If you don't want to rebuild your existing motor, which is what I would do, the next best thing is to buy another car with the same motor, which you can at least test on the road- there will be loads about for not a lot of money-and pull the motor from that!!
rashmore
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Post by rashmore »

Yeah am a little dubious about it, must admit. have been caught out when changed engine in 309 - had to take it out again as bag of nails....thanks to 28 day warranty supplier was fine about it.
Considering repairing mine just figured time wise can swap over in a weekend, where strip and rebuld will take a little longer.... just not sure what i'm going to find when strip down....
Eyes open for spares repair also
jeremy
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Post by jeremy »

If you're going to do it yourself (my preferred option) you're in for a long haul and really need some experience or a good book. You've gotto get the engine out and dismantled first. You then need to examine the bores and pistons and ascertain what the damage really is. Its probably rings but unless the thing has been overreved there must be a reason why they have failed.
What happens is that ring/bore wear allows hot gasses past the rings which get hot and eventually get brittle and break. When they break they often wear the piston in the ring groove. There may be scuff marks on the piston which may cause a problem and the bores themselves may have been scored by the broken rings.
If the bores are unworn you are looking for roundness or rather the lack of it as obviously a piston ring is designed to seal a round bore and won't work well in an oval one!
While you've got it apart the oil pump and its drive should be checked, all seals replaced and the crank removed, and its journals measured for ovality (you may get away with this one) and its shells replaced as a matter of course.
Connecting rods need to be examined to see if the bore in the top is unworn as this is the bearing with the piston.
Which is why I suggest that an already done short motor (block/crank/pistons) may be the answer. Get a copy of exchange and Mart - at least it'll give you some guide prices.
jeremy
hawk
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Post by hawk »

hi if you are going to keep the car a long time 2yrs plus i would get the bottom end recon. i bought a engine from a scrap yard once it only lasted 3 months and no back up from the scrap yard 350 quid down.
rashmore
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Post by rashmore »

Cheers Jeremy/bxbodger/Hawk
Yeah shying away from scrap/donor engine – if cannot get one from same car going to be a pain as ancillaries etc are bound to be different – eg pug 405 etc, plus warranty etc
Quite handy with a spanner so will strip myself. Got feeling will need rebore and pistons as it made horrid screeching noise – will only know when pull apart.
Checking prices for the above and re shelling the crank as a given. Will check \replace items as highlighted by Jeremy and also do cambelt while I’m at it.
Can check the head on friends miller – do I need to check this any other way ? pressure test but that means b4 strip apart but can’t move it far….mobile testers ?
Told to get head polished and ported while it off (friend got the equipment) but is this going too far ?
To look at re-cond short engine as price comparison
Thanks for help as would like to keep her going for a while longer yet - keep u posted [:)]
jeremy
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Post by jeremy »

I think the general consensus is that the standard heads have good gasflow and modification doesn't seem popular. Its certainly worth taking the valves out, cleaning upo, lapping, re-shimming and replacing the stem seals if it has any as well as other gaskets but all this depends on how far you want to go.
In my student days I re-engined a Hillman Hunter 1500 with a 1725 cc engine and simply put it in - whereupon the thing went brilliantly but it came to a halt and i called the AA who diagnosed a carb problem and tried to clear it by overrevving. he cleaned the car but it wasn't the same and eventually was burning oil at about 1 gallon per 100 miles - so I had to do something and removed the engine and stripped it - only to find that the rings on one piston had broken. Bore was not good but I had very limited funds and so I cleaned it all up, dug the carbon out of the ring grooves with broken rings, found another piston was cracked, purchased 2 pistons, new rings for the others and new shells all round and put it together.
Crank nearly locked when I put it together but I couldn't see anything wrong so I just had to hope for the best as to do anything meant a regrind and if it siezed it would need that anyway! I fired it up and let it run for about 30 secs, let it cool and did the same several times gradually letting it run a bit longer each time until I dare drive it - and it was fine for another 20K or so and extremely fast! The valves were Ok but I gave them a light grind for safety's sake and spent hours taking the rocker assembly apart, grinding the recesses out of the valve contact area and poking out the oil holes.
The funny thing was after running it in for about 500 miles I put my foot down and when I stopped there was thick smoke coming out of the back silencer - all the unburnt oil had caught fire! - I just drove it gently to try and blow it out which seemed to work and prevented a heat build up as the fuel tank was directly above!
Loads of rules broken here - I got away with it but no doubt it would have been even better if the job had been done properly!
jeremy
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Post by Peter.N. »

I dont know that I share you views of not getting an engine from the scrappers. If you can hear the engine running and give it a good examination, its going to be a lot cheaper than a recon, even if you do it yourself. The most likely serious problem would be the head gasket, check for the presence of antifreeze, stick your finger in the water and just taste it, it should be sweet, if it has antifreeze the chances are that it hasn't been blowing water out and the gasket is OK. You can check it further by by running the engine for 10 or 15 minutes and then SLOWLY and CAREFULLY removing the filler cap, there should be a small ammount of pressure but it shouldn't blow water out unless it is over full or boiling! If possible, drive the car round and see what it feels like. 136k is not a high mileage for an XUD although it is about the time for head gasket problems. Had you thought of getting a scrap car, you might get one for nothing, you then have the problem of disposing of the rest of it, but if you can manage that it could be the cheapest way.
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Post by bxbodger »

Does anyone recall CarMechanics mag article a couple of years ago on the 405 diesel they bought at auction, undriven but running- this passed all the scrapyard type tests that you can do without driving the car, and was reputedly an excellent runner with service history...... and it turned out to be an absolute dog with major cooling system problems and had to come out......which led to their two part special on XUD rebuilding......
It was all the sort of trouble that would have been avoided by a few miles drive on the road. A diesel engine started from cold and just left idling for 15-20 minutes is not going to get hot enough to even set the fans off.
I still say that you will never get a good engine from a scrapper, unless its from a pretty recent car which has obviously had major write off accident damage- and in these cases the salvagers/reconners usually get the motor.
If a car is in the yard and undamaged, in this day and age its unlikely to be corrosion thats put it there-no, i'tll be either engine or transmission failure, and if its got a manual box, and not some mega-expensive autobox, then 99% of the time it will be the engine thats gone beyond economic repair.
You won't get one out thats any better than the one you already have....
If you don't want to go the full rebuild route I still think the donor car is the best way to go- you can test drive a donor car for 2 or 3 hundred on the other hand for 15 or 20 miles and you can see how the motor behaves, if it knocks under full load,if it smokes uphill on the governor, all the sort of thing you can't check in a scrapyard. And there are a LOT of good cheap ZX's out there!!
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Post by wilkobob »

Would have thought alot of XUD's wind up in scrap yards due to head gasket failure (this is where my replacement engine came from apparently), and since the engine is out of the car, the head gasket is easily changed anyway, as is the cam belt and water pump, which in any replacement engine situation, I would do anyway as precaution. (ie, all gaskets and any belts, and the water pump)
rashmore
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Post by rashmore »

Ouch
Just got some prices for having the engine re-worked. Worst case scenario prices.
Excuse speling….
Rebore :
Hepalite Pistons £460 + vat
Carl Smidt Pistons £320 + vat
Main big end, thrust washers etc £56 + vat
Cyl Head – pressure test, skim, reseat valves, clean ,shim £122 + vat
This excludes new head bolts, full gasket set, replacement of stuff that gets broken, etc etc.
Will keep my eyes open for a replacement motor I think, and do basics on that. Else its being broken for parts - it may be a volcane td but its not that valuable to spend as much (if not more) than it is worth repairing it [:(]
trying to find more info in exchange n mart
jeremy
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Post by jeremy »

So the professional work will cost £585.15 including VAT and on top of that you will probably have £100 - £150 for belts, bolts, gaskets etc. After a lot of work you will have a car with virtually a new engine which hopefully will give you worry free fun for many years. What can you buy that will do that for that money?
jeremy
rashmore
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Post by rashmore »

The price for the rebore depends what pistons they have in stock apparently hence could be one or the other - surely i can specify seeing as i'm the paying customer....
Yes, i see your point, that was my original viewpoint, but seems everyone i've spoken to thinks differently. Afterall replacement (scrap)engine £250+, then still got to do all usual work on it to make sure it is ok....
Trying to find another machine shop for comparison......
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